Recent developments in state estimation with phasor measurements

Synchronized phasor measurement units (PMU) are being installed in many power systems around the world. Several of these installations intend to utilize the PMU data to augment features of their state estimators. This paper summarizes results of recent research which have used phasor measurements in novel ways. Beginning with a phasor based state estimation technique the paper considers an innovative approach to incorporating phasor data in conventional state estimators. The paper reviews the concept of complete and incomplete observability with phasor data, and the use of incompletely observed state to achieve pseudo observability. Also included is a discussion of seams between adjoining state estimates, and a new concept of using phasor measurements to calibrate instrument transformers.